A practical, low cost solution to monitoring charging and batteries

What is the issue?

How to keep an eye on the state of your battery at all times, at rest, in use, and when charging.

Why address this?

A low battery can mean serious problems when starting your engine or running your instruments. It can also mean a shorter battery life. If there is a problem you need to know.

How to address this?

A very simple and effective solution is to buy a basic 12volt battery and alternator tester and permanently install it on the control panel, as shown above, between switch panel and shipping forecast areas, or at another conspicuous point.

A typical 12volt battery and alternator testerPhoto: Courtesy of Litong

12volt battery and alternator testers are a very low-cost item to purchase, about the price of a modest bottle of wine, and although they do not give the detailed digital multidigit reading required to assess the state of charge, the illuminated LEDs are very good at flagging attention to a problem.

LED Battery testers are available on-line and in many Motor Factor Shops. Most LED scale indicates battery voltage (poor - red, fair - amber, good - green) and alternator output (low, normal, strong). The one I use and recommend has LEDs for six separate voltages: 5, 12, 12.5, 13, 13.5 and 14. It costs about €8!

I have had one of these permanently linked to my live battery connection for years. It tells me if the battery is switched on and lets me see from a considerable distance just what is happening. There are no buttons to press and you don't need to be a few inches from the meter to read it. In fact, you could wire one of these to each of your batteries. As with most LEDs, current consumption is minimal.

With thanks to:

Brian Lennon

A photograph is worth a thousand words. We are always looking for bright sunny photographs that illustrate this experience. If you have some images that we could use please upload them here. All we need to know is how you would like to be credited for your work and a brief description of the image if it is not readily apparent. If you would like us to add a hyperlink from the image that goes back to your site please include the desired link and we will be delighted to that for you.

Add your review or comment:

eOceanic makes no guarantee of the validity of this information, you must read our legal page. However, we ask you to help us increase accuracy. If you spot an inaccuracy or an omission on this page please contact us and we will be delighted to rectify it. Don't forget to help us by sharing your own experience.